Archery Talk Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
582 Posts
Discussion Starter #1
So I upgraded my bow recently. Went from a SF Premium 25" riser with Winstar Carbon limbs (long, 28") cranked all the way down. Drawing 30". Upgraded to Win&Win Winex riser with Win&Win 34# long RCX-100 limbs, bolts all the way out. Shooting Easton ACC, 3-18 arrows, so they should spine much better to the new bow than the old one. All the space I have to shoot for right now is 9m indoors in my hallway. So, what I don't understand is why I should have needed to LOWER my sight by over 1/2 cm (6mm to be exact) to hit the center. I also had to move the aperture significantly right, though I suspect that has to do with tuning issues.

Is it likely the elevation setting has to do with tuning as well? Or maybe the mounting holes are just placed differently? Or is 9m just too short a distance to really know any of this? I don't feel like my form has changed at all. Obviously I'm noticing the increased draw weight, but I still feel solid as far as form goes. It just seems odd that the sight would have to move down. I really didn't expect it would need to move much at all because arc is probably fairly insignificant at such a short range.

Anyway, it's all shooting fine, and I sure do LOVE the upgrade (thanks to my wonderful wife!). This is mostly a question of curiosity. Thanks.
 

·
Premium Member
Joined
·
979 Posts
Hey Ted,
Seems like you'd be shooting just 2-3 pounds more.
A few thoughts. How did you set your tiller on the SF? Same tiller setting on the W&W?
How do you set your string nocks? Are they about the same height above the button/rest now as then?
A change in either could cause your issue.
Do you have the SF riser? Measure from the sight bolt holes to the button, and compare. I would think that they would be the same.
Tough to do much tuning at 9M, I'm assuming that you also shot the SF set up at 9M, hence your question.
At issue here is whether you will have less adjustment between distances with the heavier draw, and a shot at 90M, correct?
That will have to wait.
Good shooting!
Butch
 

·
Registered
Joined
·
582 Posts
Discussion Starter #3
That's exactly my concern. Sounds stupid to worry about at this point, but yes, did I just LOSE room to adjust downward to reach longer distances. Not doing any tuning at this point. I set the tiller the same, but I'll verify anyway to be sure. Same nock height (same string). Keeping the old riser, so I'll measure tgat distance, though I assumed it'd be the same since same manufacturer, but assumptions can always be wrong.

Tiller setting is 1/8" difference. Yeah, tough to tell a lot at 9m I'm sure, but working up the weight to get out to the far distances this summer. I'll check to be sure the nock height is actually the same though, since I also made that assumption based on it being the same string, but now I'm thinking about it, there's no reason that should definitely be the case. Okay, I'll check all of that. Thanks!
 

·
Registered
Joined
·
2,406 Posts
It may be just a couple more pounds, but it sounds like the limbs are more efficent. What you are seeing is :Archer's paradox" The arrow starts out lower than your eye. With distance the flight arch rises above your eye sight, and finally falls back into the target aim point. If the arrow is fast enough, you need to lower the sight to get it up to your aim point for shorter distances. The speed of the arrow changes with arrow weight, draw weight, and limb efficency. The rate that it falls toward the earth is a constant of gravity. Unless you are playing field, then steep uphill and downhill come into play.
 

·
Registered
Joined
·
582 Posts
Discussion Starter #5
Checked the settings. Tiller is set the same as the last one (upper +1/8"). Nock height same as the last one (1/2").

Measured the plunger to sight distance. Looks like they're the same.
 

·
Registered
Joined
·
378 Posts
Sounds like the sight is just mounted differently on the riser.
Some risers mount the sight higher or lower than on others, leading to the sight marks being different.
For most sights you can just move the elevation bar up or down to compensate for this and get your full adjustment range.
 

·
Registered
Joined
·
94 Posts
If you've measured the sight difference, then I guess it isn't that. However, my old riser allowed me to bottom out my sight without fletching contact, my new riser does not, so there is definite variance in sight mount position. The other thing that may be an issue is position of the pivot point in the handle. If your old grip pivot point to plunger hole distance at a set distance resulted in an arrow angle from horizontal of some degree measure, then lengthening the distance from plunger hole to grip will cause the angle to increase, while reducing the distance from plunger to pivot will cause the angle to decrease.

If I'm not being clear, imagine this. Stand facing the backside of a right handed archer (backside meaning the archers back). If you increase the plunger-pivot hole distance to a whole foot, the arrow will be pointing with quite an angle upwards. If you decrease it to zero, or move the plunger hole BELOW the pivot, then you arrow will be pointing pretty far downwards. If you keep the sight distance to plunger distance constant, this will mean you must adjust the sight to account for this difference.

Apart from it possible being a tuning issue, the riser geometry is going to be different, so you'll probably see a difference in sight points. When I changed my riser, My sight went upwards significantly, shooting the same limbs and arrows. I did the measurements, and there was definite differences in the measurements of sight-plunger and plunger-grip pivot.

However, someone I know upgraded risers to something much heavier, and as a result, initially, he had issues with dropping his bow arm due to the heavier weight, and so moved his sight.

If you can verify that your form is still consistent, it's probably not your fault. You may need to tune your bow, however.
 

·
Registered
Joined
·
1,702 Posts
At very short distances, sight adjustments work the other way round. At few meters, I have to shoot with 50m settings.

With proper distances, things should work out.
 

·
Registered
Joined
·
582 Posts
Discussion Starter #9
Okay, so, exact same distance from plunger to grip pivot. On the other hand, the riser is heavier (.4# is the advertised), so I wonder if that's it. Hmm... Things still feel very much the same, but that's worth paying closer attention to.

I'm really stumped now as to what else it could be, so, maybe, it is a form thing. (Sigh...) I still feel confident, but maybe it's a very minor thing that'll pass with a few more days of adjusting to the change. It's only been less than a week.
 

·
Registered
Joined
·
545 Posts
reread what "RADMAN" and "ZAL" said, and think about it, at about 25M the new limbs should start having higher site-marks than your old limbs.
 

·
Registered
Joined
·
582 Posts
Discussion Starter #11
reread what "RADMAN" and "ZAL" said, and think about it, at about 25M the new limbs should start having higher site-marks than your old limbs.
Thanks guys. I did that. It took me a little while to engage the physics locked away in the back of my brain, but I did, and I made a diagram, and you're right. It would take far more work to figure out the exact numbers for distances at which the "inversion" takes place (so I'd bet your 25m suggestion is pretty close), but yes, it makes sense if you look at a diagram. At some point, sight settings WILL have to work opposite. And it makes complete sense that 9m must be well less than that distance. Especially coupled with the fact that the new limbs are: a) heavier draw weight, b) much higher quality, and c) carbon/foam instead of carbon/wood, so I'm probably getting a lot more out of them. This was an interesting exercise, and taught me a little something too. Thanks for the feedback.
 
1 - 11 of 11 Posts
Top